http://www.instructables.com/id/EYASGDSF0FI3ADK/
This is a link to a simple solar boombox I've developed.
More advanced versions have been made, but I tried to keep this as simple as possible so more people can build it.
Pekar
This is a link to a simple solar boombox I've developed.
More advanced versions have been made, but I tried to keep this as simple as possible so more people can build it.
Pekar
Nice!
I've been running my chip-amp (TDA7350) from my 10W panel,and a bank of batteries. No mains noise here. 😀
I've been running my chip-amp (TDA7350) from my 10W panel,and a bank of batteries. No mains noise here. 😀
neat idea - now I'm imagining a solar panel on top of the house... used to charge batteries to drive a bigger class D amp, and a portable CD/MP3/whatever player... and even my DAC which doesn't draw much current at all. When the clouds/rain comes there should be enough juice in the batteries to last you the night/day.
Those panels put out 24v if I'm correct, in which case you could run a low voltage tube pre-amp too, using 6GM8 tubes. I have an Aikido built that way, but no solar panels to power it.
" ... in which case you could run a low voltage tube pre-amp too ..."
Not too likely. The tube heaters will be too inefficient for the cells to maintain a decent level of power except in full sun.
Solar cells do put out a nice voltage, but solar output power falls off dramatically as the load increases. Watts is Watts ...
A very nice concept BTW: solar powered MP3 player through solid state "boom" box ... I like it, good show!!
Not too likely. The tube heaters will be too inefficient for the cells to maintain a decent level of power except in full sun.
Solar cells do put out a nice voltage, but solar output power falls off dramatically as the load increases. Watts is Watts ...
A very nice concept BTW: solar powered MP3 player through solid state "boom" box ... I like it, good show!!
1.2a* 6v total? That doesn't sound like that much. That isn't even as much as a small light bulb.
This is a very "Bright Idea!"
I have 2 of these panels now (thanks Pekar) and it works. Works pretty well, too.
Quick warning - DO NOT connect 2 or more panels in parallel, there isn't enough voltage drop.
In the mid day tropical sun, these panels put out about 23V without load. That's far too much for the little Tripath chips. But not to worry, as Pekar notes, once you put a load on the panel, the voltage drops right down. Mine drops down to about 10.5V at moderate music levels.
I am running a Lepai amp because it seems to have over-voltage protection - that's a good thing. With just one panel running, I can't go very loud on small inefficient speakers because the voltage then drops to <8V. 8V is the cut off. As the Lepai has a diode on the power input there is a 0.6V drop. That doesn't help max levels any.
Putting 2 panels in parallel brings the voltage up too high and the amp shuts down. Too bad, because the amp cold use the extra power. Guess a voltage regulator is needed for 2 panels.
Adding a stiffener cap really helps. I put on a giant 47000uF cap. Lets the amp play louder overall because it fills in the power on the bass hits. Also keeps the amp playing when a shadow crosses the panel. 47000 is huge, but it was on the self, so I tried it. Turning off the Bass boost on the CD player really helped get levels up. The speaker I was using can't really do much bass anyway (Radio Shack Optimus).
There you have it, sun worshipers. Fun in the sun for your summer project. Thanks Pekar!
Oh, how is the sound? Luminous - of course! 😀
I have 2 of these panels now (thanks Pekar) and it works. Works pretty well, too.
Quick warning - DO NOT connect 2 or more panels in parallel, there isn't enough voltage drop.
In the mid day tropical sun, these panels put out about 23V without load. That's far too much for the little Tripath chips. But not to worry, as Pekar notes, once you put a load on the panel, the voltage drops right down. Mine drops down to about 10.5V at moderate music levels.
I am running a Lepai amp because it seems to have over-voltage protection - that's a good thing. With just one panel running, I can't go very loud on small inefficient speakers because the voltage then drops to <8V. 8V is the cut off. As the Lepai has a diode on the power input there is a 0.6V drop. That doesn't help max levels any.
Putting 2 panels in parallel brings the voltage up too high and the amp shuts down. Too bad, because the amp cold use the extra power. Guess a voltage regulator is needed for 2 panels.
Adding a stiffener cap really helps. I put on a giant 47000uF cap. Lets the amp play louder overall because it fills in the power on the bass hits. Also keeps the amp playing when a shadow crosses the panel. 47000 is huge, but it was on the self, so I tried it. Turning off the Bass boost on the CD player really helped get levels up. The speaker I was using can't really do much bass anyway (Radio Shack Optimus).
There you have it, sun worshipers. Fun in the sun for your summer project. Thanks Pekar!
Oh, how is the sound? Luminous - of course! 😀
A small SLA battery might be a good idea..but would add some weight.
It would also help keep the voltage (fairly) constant ~12-13V.
It would also help keep the voltage (fairly) constant ~12-13V.
I cover most of this on instructables, but having a battery in the circuit is recommended for most applications as it regulates the voltage and keeps things Rockin' when the sun isn't present.
My preferred SLA is a 2.3 Ah bag phone battery like this one-
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=140-541&CFID=11825853&CFTOKEN=32733110
But better deals can be found.
For a smaller, lighter, higher voltage power pack, I assemble 10 cell AA NIMH packs.
I get 5.5 hours of top volume playback from a 2.5 Ah battery with no solar charging.
...actually that is with my amp6, so a Sonic Impact should play longer.
The HF solar panels put out 120 mA. If your battery is 1.2 AH (1/10C) or larger, you won't have any problems with overcharging and no charge control circuit is necessary.
Pekar
My preferred SLA is a 2.3 Ah bag phone battery like this one-
http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=140-541&CFID=11825853&CFTOKEN=32733110
But better deals can be found.
For a smaller, lighter, higher voltage power pack, I assemble 10 cell AA NIMH packs.
I get 5.5 hours of top volume playback from a 2.5 Ah battery with no solar charging.
...actually that is with my amp6, so a Sonic Impact should play longer.
The HF solar panels put out 120 mA. If your battery is 1.2 AH (1/10C) or larger, you won't have any problems with overcharging and no charge control circuit is necessary.
Pekar
41hz AMP6 has over voltage protection...
I saw flexible solar panels at http://www.conrad.nl They seem very nice for portable use...
I saw flexible solar panels at http://www.conrad.nl They seem very nice for portable use...
Sundown Update
Well... I didn't want to use a battery, that would be cheating! 😛
For practical reasons, yes, a battery would be great. But I wanted to hear pure solar music. It was fun. And very, um, illuminating.
With the very little power that these panels produce, 1.5 watts each, you are running right on the edge. If you turn up the sound too high, the voltage will drop and the amp will cut out. It's interesting to hear where and when in the music this happens. Too much bass or a loud midrange passage and the amp will cut out. The cut off point is about 8 volts on the supply.
Adding the large stiffener cap helped bring up the overall level because the cap helped fill in the peaks. The panels can supply the average current, the cap acts as a reservoir for the peaks. Thus overall level can go up.
Running 2 panels:
In my first post I warned of running 2 panels in parallel because of the over-voltage. Very true in the midday Tropical sun. But it turns out that as the day wore on and the sun dropped, I HAD to use 2 panels. And I went to an amp without the diode, so no 0.6 volt loss.
In the afternoon the voltage was holding at 12V with 2 panels for moderate levels. But the panels had to be tilted to face the sun. The changing angle of the sun made a big difference in how much power came out of the panels.
You would certainly want the most efficient speakers you can carry. It's going to make a big difference in how much SPL you can get. Maybe some efficient car speakers?
Over all, a lot of fun. Having just enough power to get by is a great teacher. It lets you hear the results right away. Things you may already "know" about power supplies become very obvious here. When the amp cuts out, there isn't much doubt that you don't have enough current!
I want to thank Pekar again for starting this thread and his project. I've wanted to do this for years, he inspired and helped me to get it done. =) A recommend project, if for nothing more than the educational fun.
Well... I didn't want to use a battery, that would be cheating! 😛
For practical reasons, yes, a battery would be great. But I wanted to hear pure solar music. It was fun. And very, um, illuminating.
With the very little power that these panels produce, 1.5 watts each, you are running right on the edge. If you turn up the sound too high, the voltage will drop and the amp will cut out. It's interesting to hear where and when in the music this happens. Too much bass or a loud midrange passage and the amp will cut out. The cut off point is about 8 volts on the supply.
Adding the large stiffener cap helped bring up the overall level because the cap helped fill in the peaks. The panels can supply the average current, the cap acts as a reservoir for the peaks. Thus overall level can go up.
Running 2 panels:
In my first post I warned of running 2 panels in parallel because of the over-voltage. Very true in the midday Tropical sun. But it turns out that as the day wore on and the sun dropped, I HAD to use 2 panels. And I went to an amp without the diode, so no 0.6 volt loss.
In the afternoon the voltage was holding at 12V with 2 panels for moderate levels. But the panels had to be tilted to face the sun. The changing angle of the sun made a big difference in how much power came out of the panels.
You would certainly want the most efficient speakers you can carry. It's going to make a big difference in how much SPL you can get. Maybe some efficient car speakers?
Over all, a lot of fun. Having just enough power to get by is a great teacher. It lets you hear the results right away. Things you may already "know" about power supplies become very obvious here. When the amp cuts out, there isn't much doubt that you don't have enough current!
I want to thank Pekar again for starting this thread and his project. I've wanted to do this for years, he inspired and helped me to get it done. =) A recommend project, if for nothing more than the educational fun.
http://www.fvgenergy.com/photovoltaic_eng/thin_film_photovoltaics.html
http://store.altenergystore.com/Sol...Sunlinq-25Watt-12V-Portable-Power-Pack/p2380/
http://store.altenergystore.com/Solar-Electric-Panels/Flexible-Rollable-Solar-Panels/c679/
They're not on the conrad site at the moment...
Note they're extremely light as well 😎
http://store.altenergystore.com/Sol...Sunlinq-25Watt-12V-Portable-Power-Pack/p2380/
http://store.altenergystore.com/Solar-Electric-Panels/Flexible-Rollable-Solar-Panels/c679/
They're not on the conrad site at the moment...
Note they're extremely light as well 😎
I read the thread a little more closely and now I know where the confusion is with my post and the reply.
I'm looking into putting a full fledged solar system into my house, and you're talking about a small portable panel. So I could power a 24v tube pre-amp without any problem on my house system, but maybe not on the portable panel.
I'm trying to get someone to come and give me an estimate for the solar installation. They must all be very busy because I can't get anybody.
I'm looking into putting a full fledged solar system into my house, and you're talking about a small portable panel. So I could power a 24v tube pre-amp without any problem on my house system, but maybe not on the portable panel.
I'm trying to get someone to come and give me an estimate for the solar installation. They must all be very busy because I can't get anybody.
I just ordered 4 of these for my 41hz amp6-basic project:
http://www.siliconsolar.com/8V--250-p-16533.html
I plan to serial and parallel connect them to get 16V output to recharge my 12Ah SLA.
These new modules from silicon solar are just perfect for DIYers. Fully encased, solder pads on the back, 4mm thick, and a great variety of modules.
http://www.siliconsolar.com/8V--250-p-16533.html
I plan to serial and parallel connect them to get 16V output to recharge my 12Ah SLA.
These new modules from silicon solar are just perfect for DIYers. Fully encased, solder pads on the back, 4mm thick, and a great variety of modules.
Pekar - great post and great website.
Checkout the post on making ferrofluid.
This stuff is fun. Remember when audio was fun?
Checkout the post on making ferrofluid.
This stuff is fun. Remember when audio was fun?
G4ME said:
Hahah, what about a wheel driven by an electromotor powered by a generator spun by the wheel?
😀
No seriously I want to use solarpower soon as well. Create a charger/protection and continuous output device for a 12V system at home and on the road. Many other things (like warm-white led lamps) can run on this supply as well. The batteries won't have to be very big to keep your house lit all night 🙂
Than perhaps a laptop, all my audio, maybe even convert a PC to run on 12Vdc (I've seen PSU boards to run a PC from 10 to 30Vdc batteries!).😎
Hi,
I agree with you, v-bro. This is not a joke, sometime you will be at the place without power grid at all.
But what panomaniac did was not a good idea for me. What is the purpose with playing the voltage drop with music level? Not for me, I will not waste my money. I will spent my money for a good music of course.
Pure solar powered? Fine, use enought parallel solar board and regulate the output. That is more reasonable. Well, good luck anyway.
I agree with you, v-bro. This is not a joke, sometime you will be at the place without power grid at all.
But what panomaniac did was not a good idea for me. What is the purpose with playing the voltage drop with music level? Not for me, I will not waste my money. I will spent my money for a good music of course.
Pure solar powered? Fine, use enought parallel solar board and regulate the output. That is more reasonable. Well, good luck anyway.
v-bro said:
How about hamster power 😀
An externally hosted image should be here but it was not working when we last tested it.
Nice job Pekar!
-Ken
- Status
- Not open for further replies.